This is great. I wondered for a while why Github doesn’t innovate in the CI space, even thought about some browser extensions myself to hack on top of Github. It seems they are stepping up a bit. But will it take over most UI features of a CI system? The re-run button is a step for sure.

The biggest blocker is that this feature is only available to Github Apps (e.g. not oauth apps) which looks to be a non-trivial change. So this is something that will need to be completed first. It is planned, but not something I have started working on yet.

The hardest part I can see is triggering a single step

The existing implementations (travis, etc) seem to only have a single check per build. If you look at the travis screenshot you will see they list each individual step in the details section (below). This means restarting the check will restart the entire build.